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View Full Version : Don't believe everything you read about DF27



razyn
11-13-2019, 08:01 PM
Really, about DF27 or anything else; misinformation is rampant, and not all sources are equal. But in this particular instance, I have just noticed this Wikipedia article: https://en.wikipedia.org/wiki/Haplogroup_R-DF27

I think the most recent update to that DF27 article was just adding the immediate upstream SNPs we know about now (mainly because Alex Williamson has added them to his Big Tree). And in itself, that's a good thing to do. But whoever else has written or edited that entry, in the past year or so, has not kept up (or just has not agreed) with more current genomic science that gets discussed often, here; and sometimes on the "activity feed" of the R-DF27 haplogroup project at FTDNA. Other sources drift a little farther afield -- but tend these days at least to have been exposed to Olalde et al (2018), and other recent papers dealing with aDNA, and the wonders revealed by testing it by NextGen sequencing.

My impression has been that anybody may edit a Wikipedia entry; but getting into an argument with another volunteer editor who has strong opinions on it would not be a good use of anybody's limited days upon the earth. Certainly not mine. Just for the record: the entry at present falls in step with Solé-Morata et al (2017b), in assuming an origin for DF27 somewhere near the northeastern corner of Spain -- because in 2012 some of (co-author) Calafell's students had checked a bunch of French and Iberian samples, for 15 STR markers or so -- and sure enough, found what the Eupedia map had already been showing for several years (mostly, about SRY2627 and M153). [One might profitably keep in mind that Rocca et al had (in 2012) just reported that there is such a thing as DF27; and even Z196 was only identified about a year earlier.] Then it took another five years or so for the paper to get written, peer reviewed, and into print. And about half an hour to critique (and dismiss) its main conclusion. Which is kind of a shame; really the same data could have proven something -- just not that DF27 was born in the Pyrenees. https://anthrogenica.com/showthread.php?827-Where-did-DF27-originate-and-when-and-how-did-it-expand&p=292110&viewfull=1#post292110

A bigger problem than one paper (by grad students at an Iberian university, spending government funds, on a short timeline) is that heat maps don't prove anything about origins. But such maps rarely include any such disclaimer; and even if they did, they would tend visually to lead people to focus on the wrong end of a timeline that is several thousand years long. There's one in this Wikipedia article, for example.